As of writing, it links to the last comment on the original question, which would normally be hidden.

There's a link just below saying add / show 1 more comment, but there is no other comment.

It seems like it's not expanding the comments in a consistent way.
The UI should look the same whether I browsed to the question, and clicked show more, or whether I clicked on a comment link to a hidden comment.

@kiamlaluno: Do either of you have an account there? Possibly that's why you get something other than what I get. In either case it doesn't seem right (when logged in it says there's another comment, but there isn't and when not logged in it says you can add a comment).
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George DuckettJan 31 '12 at 16:34

I have an account there. The fact Tim Stone doesn't have an account there suggests that is not what makes the difference.
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kiamlalunoJan 31 '12 at 16:44